Lateral bend power-driven conveyer



A. 10, 1948. F. STADELMAN LATERAL BEND POWER-DRIVEN CONVEYER 2 Sheets-Sheet 1 Filed Oct. 21, 1946 IZVEQITOR.

id @(Z- ATTORNEY Aug. 16, 1948. F. STADELMAN 2,445,390

LATERAL BEND POWER-DRIVEN CONVEYER Filed Oct. 21, 1946 2 Sheets-Sheet 2 ATTORNEY Patented Aug. 10, 1948 LATERAL BEND POWER-DRIVEN CONVEYER 7 Frank Stadelman, Cranford, N. J., assignor to Latendorf Conveying Corporation, Bayonne, N. J a corporation of New Jersey Application October 21, 1946, Serial No. 704,760

1 8 Claims.

The present invention relates to conveying systems and it relates more particularly to conveyors of the endless belt type.

An object of the present invention is to provide a new and improved conveyor which is simple, inexpensive and efiicient in construction and operation. Another object of the present invention is to provide an endless-belt type conveyor which operates with minimum wear and power loss and which is equally well adapted for use on straight runs and around curves.,

Other objects and advantages of the present invention are apparent in the following detailed description, appended claims and drawings.

The present application is a continuation-inpart of my co-pending application Serial No. 534,455, filed May 6, 1944, now Patent No. 2,413,- 339, issued Dec. 31, 1946, wherein I have disclosed and claimed, inter alia, a conveyor including a flexible endless belt comprising a web of interconnected elements, having freedom for transversely-differential lengthwise expansion and contraction, arranged in a working run and a return run, a bed supporting the working run and including a laterally-curved portion, and driving means engaged with the return run only of the belt for pulling said return run, the web of said belt being longer than the combined lengths of the Working and return runs whereby a slack zone is formed immediately in front of said driving means and whereby the working run is loosely disposed on said bed so that the interconnected elements are free to expand and contract around the laterally-curved portion of the bed.

I have now found that, with conveyors employing relatively wide belts (for example, belts having a'transverse dimension of three feet or more), wear and failure of the belt links can be further reduced by provision of certain novel movable guiding means disposed along the inner periphery of the bend along which the conveyor belt moves.

For the purpose of illustrating the invention, there is shown in the accompanying drawings one form thereof which is at present preferred, although it is to be understood'that the various instrumentalities of which the invention consists can be variously arranged and organized and that the invention is not limited to the precise arrangements and organizations of the instrumentalities as herein shown and described.

Referring to the accompanying drawings, in which like reference characters indicate like parts throughout:

accompanying Fig. 1 represents a schematic perspective view of one embodiment of the present invention.

Fig. 2 represents a fragmentary perspective view, on an enlarged scale, of the embodiment of Fig. 1.

Fig. 3 represents a fragmentary plan view showing a portion of the curved part of the upper or working run of the conveyor of Figures 1 and 2.

Fig. 4 represents a. cross-sectional view generally along the line 4-4 in Fig. 3.

Fig. 5 represents a fragmentary schematic top plan view illustrating the configuration of the transverse links of the conveyor belt during the straight portion of the working run and also during the curved portion of the working run.

Fig. 6 represents a fragmentary schematic top plan view generally similar to that of Fig. 5 but showing the configuration of the transverse links of the conveyor belt as they would appear if the inner peripheral omitted.

In one embodiment of the present invention shown generally in Figures 1-6, I may provide a conveyor frame, indicated generally by the reference character ill, and provide wtih an upper working bed II and a lower return bed I2, shown particularly in Fig. 2.

The bed H has straight end portions l3 and I4 and an intermediate curved portion l5 which may extend through of are, or through any other suitable angle; the return bed, l2 being similar in shape.

An endless flexible conveyor belt It, the construction of which is shown and described par-. ticularly in my co-pending application Serial No. 534,455, is mounted upon the beds H and i2 as shown in Figures 1 and 2. The belt I6 is made up of relatively inflexible transversely-extending metal links which are woven inter-engagedly to permit longitudinal expansion and contraction of the belt and to permit the links to assume either parallel relationship (when the belt is disposed upon a straight run) or a generally radial relationship (when the belt is disposed upon a curved run).

As shown particularly in Fig. 2, the straight portion l3 of the upper working bed ll extends somewhat beyond the end of the return bed I 2 and driving means are provided thereunder for said belt it. The driving means includes a pair of juxtaposed rubber-surfaced driving rolls l1 and I8. The upper roll I! is a power roll being driven by motor l9 through a belt 20; conventional speed-reduction gearing (not shown) being promoving guide -chain were vided, optionally, intermediate the motor I! and the roll I].

The lower roll I. is an idler back roll which is rotatably mounted on a shaft 24 which is urged upward by coil springs 2! bearing against its ends, so that the roll I I presses the intervening portion of the belt I. up against the roll II, thereby providing a friction drive for said belt.

As can be seen particularly in Figures 1 and 2, the belt I8 is made somewhat oversized in length relative to the total length of the beds II and I! so that a relatively slack loop 28 is formed therein immediately in front of the driving rolls I1 and I I the belt passing from the loop It over the edge of the portion II of the upper bed II to enter its working run. The belt passes from the other end of the working run downward to the return run, as indicated particularly in Fig. 1, without any appreciable slack loop.

Retaining walls or shoulders 29 are provided along the inner edges of the portions I2 and it of the bed I I. Retaining walls 30 may be provided along th outer edges of the portions I3 and II. The lower bed I2 may be provided with similar inner and outer retaining walls.

As more fully described in my co-pending application Serial No. 534,455, the slack loop 26 permits the belt It to be pulled along the bed II on its working run, in relatively slack condition. This reduces friction and wear, as compared to conventional taut-belt constructions heretofore employed, and permits the belt to adapt itself to the curved portions of the working and return beds as well as to the straight portions thereof.

According to th present invention, it has been found that, with relatively wide belts (for ex- 7 ample, belts having transverse dimensions of three feet or more), the individual links, instead of assuming the true radial configuration when passing along a curve, actually assume the configuration shown in solid lines in Fig. 6, if a fixed retaining wall or shoulder is provided along the inner edge of the curve as disclosed in my copending application Serial No. 534,455. That is. with such a fixed retaining wall or shoulder at the inner edge of the curve, the inner ends of the individual links tend to lag behind the outer edges of the links so as to form an angle from the true radial position, which is indicated in dash-dot lines in Fig. 6. It will be noted that this angle, which may be designated as the angle-of-lag, increases from a relatively small value at the beginning of the bend to an appreciably larger angle which is maintained throughout the course of the bend. It has been found that with relatively wide belts. as discussed above. this oil-radial posi tioning of the individual links as the belt moves along the bend, tends to create undue stress and wear upon the belt such as may cause premature failure of the belt.

Accordingly, the present invention contemplates provision of novel moving guide-means disposed along the inner periphery of the bend of the conveyor so as to provide a supporting surface, moving in the same direction as the conveyor belt, and at generally the same speed, so as to minimize the lag in the belt links and to insure their positioning in substantially radial relationship, thereby appreciably to lengthen the useful life of the wide-belt conveyors of the type described hereinabove.

As shown particularly in Fig. 2, the novel moving guide means of the present invention includes upper and lower continuous sprocket chains IIIII and IOI extending generally along the inner pcworking and return runs of the conveyor belt.

The chains I00 and IOI pass over loose sprocket wheels I01 and I" at their other ends.

The sprocket chains Hill and IUI are adapted to be driven by the motor I9 generally in synchronization with the conveyor belt. That is, the upper chain I" is adapted to be driven so that its outer periphery moves generally from left to right in Fig. 2 and at approximately the same speed as that of the inner periphery of the conveyor belt moving on its working run. Similarly, the lower sprocket chain IN is adapted to be driven so that its outer run moves from right to left in Fig. 2 at generally the same speed as that of the inner periphery of the conveyor belt moving on its return run. I

While I prefer to synchronize the sprocket chains so that their speeds are substantially identical with the correspondingly moving inner peripheries of the conveyor belt, the present invention is not so limited and also contemplates the movement of the sprocket chains at slightly greater or slightly lesser speeds.

As shown particularly in Figures 3 and 4, the sprocket chains are in frictional contact with the inner peripheries of the conveyor belt. Thus,

in addition to providing radial support for the inner peripheries of the conveyor belt at the curves, the sprocket chains, by moving in the same direction and at generally the same speed as the conveyor belt, minimize the friction or drag which would necessarily result if a fixed immovable inner peripheral support or shoulder were used and thereby eliminates the principal cause for the lag in individual belt links, as described above.

Thus, with the moving sprocket chains used as inner peripheral guiding means for the conveyor belt, it has been found, that even with relatively wide conveyor belts, the angle-of-lag of the individual belt links is kept to a minimum value which is unobjectionable and which does not cause premature failure of the belt.

It has been observed that, in actual use, the conveyor of the present invention continuously and automatically adjusts itself so that the individual belt links are disposed generally in true radial position when passing along the curved portion of the run.

That is, when the conveyor belt passes along the curved portion of the working run or the return run, the individual links are observed continually to make minute angular adjustments; the inner ends of the links continually "inching up" from a relatively small angle-of-lag to more or less their true radial position. Apparently, when the moving sprocket chains are used as inner peripheral guides for the conveyor belt, the inner ends of the conveyor belt links cannot lag behind their true radial position by more than an extremely slight angle, after which the contiguous portion of the sprocket chain frictionally moves the lag ends of the links to approximately their true radial position. This is illustrated, schematically,in Fig. 5 wherein the dash-dot lines indicate the true radial positions and wherein the solid lines indicate the maximum lagging position or the individual links. The maximum angle-of-lag, which has been exaggerated for purposes of illustration, can be seen to be substantially less than the angle-of-- illustrated in Fig. is the maximum angle-of-lag and that the .mean angle is somewhat of the order of half the maximum angle due to the inching up. of the inner ends of the individual links which would cause the links momentarily to assume approximately the true radial position before again momentarily lagging topthe maximum lag position shown in Fig. 5.

It is again stressed that the solid line positions in Figures 5 and 6 are purely schematic representations of the positions pf individual links making up the conveyor belt. Actually, the links are relatively closely interwoven as disclosed particularly in Figures 6 and 7 of my co-pending application Serial N0. 534,455.

While, for purposes of illustration, the immovable guide means has been described herein as a sprocket chain, the present invention is not so limited and comprehends the alternative use of other types of flexible guiding means; as for example, belts of leather or rubber or the like, or continuous loops of flexible ribbon-steel, etc.

As indicated hereinabove, the movable. guiding means of the present invention is adapted equally well for use with conveyors having curved portions of lesser and smaller extent than the 90- curve shown in the embodiment of 'Fig. 2. For example, the conveyor of the present invention could be constructed with one or, more turns extending through 30, 45, 60, 120, 180, 270", etc.

The conveyor of the present invention can also be constructed without the straight endportions of the embodiment of Fig. 2, so that its entire working and return runs would be curved.

The inner peripheral moving guide means of the present invention can also be used with spiral: type conveyors, such as that shown, for example, in Fig. 5 of my co-pending application Serial No. 534,455. 3'

It should be noted that the novel inner peripheral moving guide-means of the present invention does not constitute a drive for the conveyor belt. That is, the moving guide-means of the present invention make no positive intermeshing engagement with the conveyor belt and are not provided with sufficient power to drive the conveyor belt, frictionally or otherwise.

Thus, in the embodiment of Fig. 2, for example, the sole driving power for the conveyor belt is provided by the rolls l1 and I8, as described above; the only function of the sprocket chains Hill and illl being to cause movement of the inner peripheral ends of the individual links, relative to the outer peripheral ends of said links; the links as a whole being pulled along the conveyor beds by the rolls l1 and I8.

The present invention is also not limited to the specific driving means (that is the rolls l1 and i8) shown in Fig. 2. Instead the present invention contemplates the provision of any suitable type of driving means (for example, sprocket wheels or chains intermeshingly engaging the links of the conveyor belt, etc.) which will leave the conveyor belt in the relatlvely slack" condition necessary to permit the'indi-vidual links to assume the radial configurationalong' a curve. in addition to parallel relation along astraight The present invention may be embodied in other specific forms without departing from'the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference beingjhadto the appended claims rather thant'o the foregoing description to indicate the scope of 'the' invention.

Having thus described my invention, I claim as new and desire to protect by LettersfPatent:

1. In a conveyor, a flexible endless belt comprising a web of interconnected elements having freedom for transversely-difi'erential lengthwise expansion and contraction arranged in a working run and a return'ru'ma'bed supporting the working run and inciudinga curv'edportion, driving means operatively engaging.sald

belt whereby'the working is 'loosely disposedon said bed sothat the interconnected elements are free to expand and contract around the laterally-curved portion of said bed, and movable guiding means extending in generally continuous contact withj thefinner periphery of said .belt along the curvedportion thereof, said guiding means beingadapted to provide an inner supporting surface moving in the same direction and at-genjerally the same speed as the inner periphery 'ofsai'd belt.

2. In a conveyor, a fi exiblefendlessbeltconiprising a web of interconnectedelements having freedom for transversely-differential lengthwise expansion and contraction arranged in a working run and a return run; a .bedsupporting the working run and including; a. curved portion, driving means 'operatively engaging said belt whereby the working run is loosely disposed on said bed so that the interconnected elements are free to expand and contract around'the laterally-curved portion of said bed, a. flexible guide-chain or the like extending along] the. me ner periphery of the curve infsaid'workingfrun inirictional Contact with saidsbe t; and meanslfor driving said guide-chain in the'jsamej direction and at generally the same, speed asthe inner pe riphery of the curved portiono'f saidworking 3. Ina conveyor, -a fiexibl'e en essfbltfcom prising a Web of interconnected elementshaving freedom for transversely-difi'erential lengthwise expansion and contraction arranged in a working run and a return run, a bed supporting the working run and including a curved portion, driving rolls frictionally engaging said belt whereby the working run is loosely disposed on said bed so that the interconnected elements are free to expand and contract around the laterally-curved portion of said bed, a motor for driving said driving-rolls, a flexible guide-chain or the like extending along the curved portion of said working run, in generally continuous contact with the inner periphery of said belt, and means for driving said guide-chain from said motor, generally in synchronization with said belt.

4. In a conveyor, a flexible endless belt comprising a web of transversely-extending interconnected links having freedom for transverselydifferential lengthwise expansion and contraction arranged in a working run and a return run, a stationary bed for said working run including a curved portion, a similar bed supporting said return run and disposed in vertically-spaced relationship thereto, driving means for moving said belt along said beds in loosely disposed position so that the interconnected links are free tourpand and contract along the curved portions of said bed, movable guiding means disposed along ing run and a return run, a bed supporting the working run and including a laterally-curved portion, driving means engaged with the return run only of the belt for pulling said return run, the web of said belt being longer than the combined lengths of the working and return runs whereby a slack zone is formed immediately in front of said driving means and whereby the working run is loosely disposed on said bed so that the interconnected elements are free to expand and contract around the laterally-curved portion of said bed, movable guide-means extending along the inner edge of the laterally-curved portion of said bed, in generally continuous contact with said belt, and means for driving said guide-means in the same direction and generally at the same speed as the adjacent portion of said belt.

6. In a conveyor, 9. flexible endless belt comprising a web of interconnected elements having freedom for transversely-differential lengthwise expansion and contraction arranged in a working run and areturn run, a bed supporting the working run and including a straight portion and a laterally-curved portion. driving means engaged with the return run only of the belt for pulling said return run, the web of said belt being longer than the combined lengths of the working and return runs whereby a slack zone is formed immediately in front of said driving means and whereby the working run is loosely disposed on said bed so that the interconnected elements are free to expand and contract around the laterally-curved portions of said bed and are free to assume a straight-line configuration along the straight portion of the bed, movable guidemeans extending along the inner edge of the laterally curved portion of said bed, in generally continuous contact with said belt, and means for driving said guide-means in the same direction and generally at the same speed as the adjacent portion of said belt.

7. In a conveyor, a flexible endless belt comprising a web of interconnected elements having freedom for transversely-diiferential lengthwise expansion and contraction arranged in a working run and a return run, a bed supporting the working run and including a laterally-curved portion, a second bed supporting the return run, driving means engaged with the return run only of the belt for pulling said return run, the web of said belt being longer than the combined lengths of the working and return runs whereby a slack zone is formed immediately in front of said driving means and whereby the working run is loosely disposed on said bed so that the interconnected elements .are free to expand and contract around the laterally-curved portion of said bed, movable guide-means extending along the inner edge of the laterally-curved portion of said bed, in generally continuous contact with said belt, and means for driving said guide-means in the same direction and generally at the same speed as the adjacent portion of said belt.

8. In a conveyor, a flexible endless belt having a working run and a return run, said belt comprising a web of interconnected elements having freedom for transversely-differential lengthwise expansion and contraction, a bed supporting said working run, said bed having a curved and a straight portion, driving means operatively engaging said return run adjacent both ends thereof, the length of said belt being greater than the combined lengths of the working and return runs whereby a slack zone is formed immediately in front of each of said driving means and whereby the working run is loosely disposed on said bed and is free to conform to the curved as well as a straight portion of said bed, movable guide-means extending along the inner edge of the laterally-curved portion of said bed, in generally continuous contact with said belt, and means for driving said guide-means in the same direction and generally at the same speed as the adjacent portion of said belt.

FRANK STADELMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

